Non-static methods can't be referenced as Callables from static methods

[KoBeWi]

Tested versions

4.3 dev6 broken
4.3 dev5 works

System information

Windows 10.0.19045 - Vulkan (Forward+) - dedicated NVIDIA GeForce GTX 1060 (NVIDIA; 31.0.15.4633) - Intel(R) Core(TM) i7-7700HQ CPU @ 2.80GHz (8 Threads)

Issue description

extends Node

func _ready() -> void:
	static_method()

static func static_method():
	print(not_static)

func not_static():
	pass

Running this script in dev5 prints Node::not_static. Running in dev6 results in Invalid access to property or key 'not_static' on a base object of type 'Nil'.. The callable is not accessible even if you name the script and do ClassName.not_static.

Steps to reproduce

1. Run the code above in 4.3 dev5
2. Run the code above in 4.3 dev6

Minimal reproduction project (MRP)

See above.

[akien-mga]

CC @dalexeev @vnen

[dalexeev]

I think the old behavior is also incorrect, non-static members should not be accessible in a static context, there should be an analyzer error. If you try to call not_static() you will get the error Cannot call non-static function "not_static()" from static function "static_method()"..

[KoBeWi]

I was using it to obtain method name, i.e. Engine.get_main_loop().call_group(GROUP_NAME, not_static.get_name()). The alternative is hard-coding &"non_static", which is less safe.

btw I forgot to mention that the new error is runtime-only. It doesn't appear in the editor.

[akien-mga]

Looking at the changelog, I suppose this might have been caused by #90223 ?

[dalexeev]

Looking at the changelog, I suppose this might have been caused by #90223 ?

Yes, most likely. But I think this is a valid assumption for the compiler, we should not allow static access to non-static members at the analyzer level.

[vnen]

Yeah, the old behavior was wrong. For a Callable you need an object and a method name, but in a static constant there's no object.

Maybe we can consider adding a nameof or something for this case if it's needed (see godotengine/godot-proposals#837). But I don't think reverting to old behavior is a good idea.

Not showing the error in-editor is another issue and should be fixed too.

[KoBeWi]

I didn't test after the fix, because I assumed it was working, but seems like instead of allowing it, the fix just made the error appear in the editor too. Was that intended?

[dalexeev]

@KoBeWi Yes, that's how it was intended. GDScript functions and Callables are not the same as function/method pointers. You can't access a non-static member of a class in a static context. #91412 only fixed an analyzer bug. The previous behavior was unintentional and was removed with the optimization for static methods in #90223.